Jamieson, Fausset & Brown

the brother, whose praise is in the gospel--whose praise is known in connection with the Gospel: Luke may be meant; not that "the Gospel" here refers to his written Gospel; but the language implies some one well known throughout the churches, and at that time with Paul, as Luke then was (Act 20:6). Not a Macedonian, as appears from Co2 9:4. Of all Paul's "companions in travel" (Co2 8:19; Act 19:29), Luke was the most prominent, having been his companion in preaching the Gospel at his first entrance into Europe (Act 16:10). The fact that the person here referred to was "chosen of the churches" as their trustee to travel with Paul in conveying the contribution to Jerusalem, implies that he had resided among them some time before: this is true of Luke, who after parting from Paul at Philippi (as he marks by the change from "we" to "they," Act 16:11) six years before, is now again found in his company in Macedonia. In the interim he had probably become so well known that "his praise was throughout all the churches." Compare Co2 12:18; Plm 1:24. He who is faithful in the Gospel will be faithful also in matters of inferior importance [BENGEL].